More than anything, the ability to do different sized ads and/or different ad fulfillments (ex. one ad campaign/creative runs 30K impressions and another ad campaign/creative runs 20K impressions, all for the same advertiser) using duplication of an ad asset to retain the ad positions and impression deliveries, clickthrough URLs, names, etc. would be fantastic.

We can probably build something that copies an asset since we do this in editorial - however - you would not be able to change the kind of asset. For example, you could duplicate a banner ad asset, but you would not be able to change to a Flash creative. Given that limitation, would this still be a useful change?